Fire and temperature alarm or indicator.



0. SMITH. FIRE AND TEMPERATURE ALARM 0E INDICATOR.

APPLICATION FILED SEPT.11, 1908.

Patented Sept. 14, 1909.

UNITED STATES PATENT JE.

CHARLES SMITH, OF SOUTH GROYDON, ENGLAND.

FIRE AND TEMERATURE ALARM OR INDICATOR.

Application filed September 11, 1908.

To all whom it may concern:

Be it known that I, CHARLES SMITH, a subject of the King of GreatBritain, residing at South Croydon, in the county of Sun rey, England,have invented certain new and useful Improvements in Fire and Termperature Alarms or Indicators, and of which the following is aspecification.

In the specification of my prior United States Patent No. 867681 datedthe 8th October, 1907, I have described a tensioned flexible connectionextending to and passing at some point in its length around the exteriorperiphery of a fusible member which is thus wholly supported by the saidflexible connection, and by passing around the fusible member theflexible connection is shortened in length. The fusible member isgenerally constructed in annular or wheel form, the flexible connectionsuch as a wire passing around the periphery of the said wheel or ring.The connection may continue and pass around in its course other similarfusible members if desired, and is then connected to an electric circuitclosing or breaking device which operates upon the extension of theconnection permitted by the softening or melting of the fusible member vthrough the action of heat. Thus the flexible connection may be fixed atone of its ends to a stationary support, and after pass ing around oneor numerous fusible rings it may be extended over a pulley at its otherend and be connected to and tensioned by a weight. Upon one or more ofthe rings fusing, the weight naturally descends and operates theelectric devices. The flexible connection I employ, generally consistsof a braided wire having great tensional strength and flexibility. Nowit has been suggested that a continued strain of the flexible connectionaround the periphery of a member such as a metal ring of fusible alloy,may produce a deformation of the said fusible member-hereinafter termedring-and this change of form may continue until it permits of such anincrease of the effective length of the flexible connectionhereaftertermed wire as to perhaps cause a fire alarm to be given, orthe wire ithas been suggested might in time owing to the continued strain upon thering of fusible alloy or upon ears or flanges formed thereon andtherewith. bend apart those flanges or ears and so permit of the wirepassing off of the ring, and so becoming increased in its ef-Specificaticn of Letters Patent.

Patented S pt. 1st, 191M).

Serial no. 452,645.

fective length, with the result before mentioned.

The object therefore of the present invention is to render suchdeformations of the metal rings of fusible alloy, if such be probable,absolutely impossible, by relieving the fusible alloy ring entirely fromthe burden due to the tension of the wire. To this end therefore andaccording to the present invention, I provide a built-up or compositering in which the tension of the wire passing around it is received by aring or band of harder or tougher metal than the fusible metallic alloywhich I employ for the body of the ring, while flanges of similar hardermetal, such for instance as brass, entirely separate from the body offusible metal and from the bearing ring or band, are em ployed. lVithsuch a structure the wire is passed around the periphery and rests uponthe bearing ring and is retained thereon by the flanges, so that thetension of the wire is not in any way borne by the fusible body portion,and the latter can be left for an indefinite time suspended by thetensioned wire, without any sign of change taking place, as I have foundby practical experi ment. hen the temperature around such a compoundring rises to about the predetermined temperature at which the fusiblemetal softens or melts, then upon such taking place the body portioncollapses, and the bearing ring and its separate flanges sepa rate, andfly apart, so instantaneously releasing the loop of wire which surroundsthe bearing ring. Such broadly are the general characteristics of thepresent invention, and I do not limit myself to the precise sections ofeither the body ring, the bearing ring, or the flanges, but to give abetter illustration of this invention I will describe a specific examplewith reference to the accompanying drawings Figure l is an elevationillustrating diagrammatically the general arrangement and mode ofemploying the rings hereafter described. Fig. 2 is a horizontal sectionof one of my improved rings drawn to a larger scale than the previousfigure, and Fig. 8 is a plan view of the ring with the wire or braidedmetallic cord in position thereon. Fig. 4: is an elevation showing oneof the flanges detached. Fig 4* is a vertical cross section through theflange shown in Fig. l. Fig. 5 is an elevation showing the bearing ringdetached and Fig. 5 is a vertical cross section through the bearing ringshown in Fig. 5. v

In constructing my improved composite fusible. ringl as shown at Fig; 1,I provide a bearing ring 2 Figs. 2, 5, and 5* of brass or some othermetal of suflicient strength, which is substantially of rectangularsection, and then I also provide two separate disk-like rings 3, Figs.2, 4, and P, to form the flanges. The flanges 3 are then placed incontact with the edges of the bearing ring 2 so as to form between thethreeparts an annular trough, and a ring elof fusible alloy is thenformed, by casting, on the interior periphery of the flanges 3 and ofthe bearing ring 2, which fusible alloy ring at retains the bearing ring2 and is extended outward slightly so as to come above the interioredges of the flanges 3, whereby the said flanges 3 and the bearing ring2 are held together and in position.

It will be obvious that when heat is applied and the fusible metal ring4: softens or melts nothing remains to hold together the flanges 3 andthe bearing ring 2, and they fly apart and release the wireinstantaneously as I have proved by many experi ments.

From the diagrammatic view at Fig. 1 it will be readily understood thatone end 7 of the braided metallic cord or wire 6 is firmly attached tosome stationary point, and that throughout its length the cord passesover one or many of such fusible rings as I have described, and thatthen its other and free end is attached to for instance a weight 8 suchas shown, or some other means by which the cord is held in tension, andsuitable devices are providedsuch as two electric contacts 9illustratedby which the descent of the weight due to the elongation ofthe cord completes an electric circuit 10 and sounds an alarm 11.

Vhat I claim as my invention and desire to secure by Letters Patentis 1. In an automatic fire and temperature alarm; the combination with acomposite member composed of a ring of metallic alloy fusible at acomparatively low temperature, an outer band of harder metal onlyfusible at a much higher temperature than said ring and surrounding theouter periphery of the latter, two separate flanges in the form ofannular plates of hard metal similar to said band, said flanges beinglocated upon said fusible ring one on each side of said hard metal band,and flanges of easily fusible metal on said fusible ring to hold saidhard metal band and flanges together; of a flexible cord, means forholding one end of said cord stationary, a normally open electriccircuit, and means acting upon the opposite end of said cord to maintainthe latter in tension, said cord passing around the external peripheryof said hard metal band and being located between said hard metalflanges to reduce the eflective length of said cord, and to support saidcomposite member until the inner fusible-ring becomes fused and saidcord is thereby released by the separation of said band and hard metalflanges, and adapted to complete the? electric circuit by the extensionin length of said cord, sub stantially as set forth.

2. In an automatic fire and temperature alarm; the combination with acomposite member composed of a ring of metallic alloy fusible at acomparati\-*ely low temperature, an outer band of harder metal fusibleat a higher temperature than said ring and sur rounding the outerperiphery of the latter, two separate flanges in the form of annulardished plates of hard metal similar to said band, said flanges beinglocated upon said fusible ring one on each side of said metal band, theconcave faces of said flanges being located opposite to each other, sothat the space between the peripheries of said flanges is less than thewidth of the hard metal band, and flanges of easily fusible metal onsaid fusible ring to hold said hard metal band and flanges together; ofa flexible cord, means for holding one end of said cord stationary, anormally open electric circuit, and

means acting upon the opposite end ofsaidqaj;

cord to maintain the latter in tension, said cord passing around theexternal periphery of said hard metal band and being located betweensaid hard metal flanges to reduce the effective length of said cord andto support said composite member until the inner fusible ring becomesfused and said cord is thereby released by the separation of said bandand hard metal flanges, and adapted to complete the electric circuit bythe extension in length of said cord substantially as set forth.

3. In an automatic fire and temperature alarm; the combination with acomposite member composed of a ring of metallic alloy fusible at acomparatively low temperature, an outer band of harder metal fusible ata higher temperature than said ring and surrounding the outer peripheryof the latter, two separate flanges in the form of annular dished platesof hard metal similar to said band, said flanges being located upon saidfusible ring one on each side of said metal band, the concave faces ofsaid flanges being located opposite to each other, so that the spacebetween the peripheries of said flanges is less than the width of thehard metal band, and flanges of easily fusible metal on said fusiblering to hold said hard metal band and flanges together; of a flexiblecord, means for holding one end of said cord stationary, a pulley at adistance from said stationary end of said cord over which pulley saidcord passes, a weight attached to the pendent end of said cord tomaintain 9s4,225 as the latter in tension, said cord between said alarmand in combination, a fusible body a stationary end and said pulleypassing around the external periphery of said hard metal band of saidcomposite member and being located between said hard metal flanges toreduce the effective length of said cord and to support said compositemem her, two electric contacts located below said weight and adapted tobe electrically connected upon the descent of said weight, an electriccircuit connected with said electric contacts and an alarm device insaid circuit actuated upon the descent of said weight permitted by theextension of said cord due to the separation of the parts of saidcomposite member upon the fusing of its fusible ring, substantially asset forth.

at. In an automatic fire and temperature multi-part device the membersof which pass immediately around the said fusible body and are separableupon the fusing of the said fusible body, a cord passing through saiddevice, a normally open electric circuit and means for effecting tensionon said cord and whereby the said electric circuit is closed when thetension on the said cord is released by the fusing of said fusible bodyand the separation of the members of said device.

In witness whereof I have hereunto set my hand in the presence of twowitnesses.

CHARLES SMITH.

Vitnesses THOMAS W. Rosnas, VVILLIAM A. MARsHALL.

